nomeata, 
At my talk at #ICFP2023 I claimed that with observable sharing one can write a parser combinator library where left-recursion works (in the presence of sharing), and someone asked if I had, and I had to admit I hadn’t, so the next day I did:
https://www.joachim-breitner.de/blog/807-Left_recursive_parser_combinators_via_sharing
#Haskell
